#include "zgl.h"
#include "msghandling.h"

void glopViewport(GLContext* c, GLParam* p) {
  int xsize, ysize, xmin, ymin, xsize_req, ysize_req;

  xmin = p[1].i;
  ymin = p[2].i;
  xsize = p[3].i;
  ysize = p[4].i;

  /* we may need to resize the zbuffer */

  if (c->viewport.xmin != xmin || c->viewport.ymin != ymin || c->viewport.xsize != xsize ||
      c->viewport.ysize != ysize) {
    xsize_req = xmin + xsize;
    ysize_req = ymin + ysize;

    if (c->gl_resize_viewport && c->gl_resize_viewport(c, &xsize_req, &ysize_req) != 0) {
      gl_fatal_error("glViewport: error while resizing display");
    }

    xsize = xsize_req - xmin;
    ysize = ysize_req - ymin;
    if (xsize <= 0 || ysize <= 0) {
      gl_fatal_error("glViewport: size too small");
    }

    tgl_trace("glViewport: %d %d %d %d\n", xmin, ymin, xsize, ysize);
    c->viewport.xmin = xmin;
    c->viewport.ymin = ymin;
    c->viewport.xsize = xsize;
    c->viewport.ysize = ysize;

    c->viewport.updated = 1;
  }
}

void glopEnableDisable(GLContext* c, GLParam* p) {
  int code = p[1].i;
  int v = p[2].i;

  switch (code) {
    case GL_CULL_FACE:
      c->cull_face_enabled = v;
      break;
    case GL_LIGHTING:
      c->lighting_enabled = v;
      break;
    case GL_COLOR_MATERIAL:
      c->color_material_enabled = v;
      break;
    case GL_TEXTURE_2D:
      c->texture_2d_enabled = v;
      break;
    case GL_NORMALIZE:
      c->normalize_enabled = v;
      break;
    case GL_DEPTH_TEST:
      c->depth_test = v;
      break;
    case GL_POLYGON_OFFSET_FILL:
      if (v)
        c->offset_states |= TGL_OFFSET_FILL;
      else
        c->offset_states &= ~TGL_OFFSET_FILL;
      break;
    case GL_POLYGON_OFFSET_POINT:
      if (v)
        c->offset_states |= TGL_OFFSET_POINT;
      else
        c->offset_states &= ~TGL_OFFSET_POINT;
      break;
    case GL_POLYGON_OFFSET_LINE:
      if (v)
        c->offset_states |= TGL_OFFSET_LINE;
      else
        c->offset_states &= ~TGL_OFFSET_LINE;
      break;
    default:
      if (code >= GL_LIGHT0 && code < GL_LIGHT0 + MAX_LIGHTS) {
        gl_enable_disable_light(c, code - GL_LIGHT0, v);
      } else {
        /*
      fprintf(stderr,"glEnableDisable: 0x%X not supported.\n",code);
      */
      }
      break;
  }
}

void glopShadeModel(GLContext* c, GLParam* p) {
  int code = p[1].i;
  c->current_shade_model = code;
}

void glopCullFace(GLContext* c, GLParam* p) {
  int code = p[1].i;
  c->current_cull_face = code;
}

void glopFrontFace(GLContext* c, GLParam* p) {
  int code = p[1].i;
  c->current_front_face = code;
}

void glopPolygonMode(GLContext* c, GLParam* p) {
  int face = p[1].i;
  int mode = p[2].i;

  switch (face) {
    case GL_BACK:
      c->polygon_mode_back = mode;
      break;
    case GL_FRONT:
      c->polygon_mode_front = mode;
      break;
    case GL_FRONT_AND_BACK:
      c->polygon_mode_front = mode;
      c->polygon_mode_back = mode;
      break;
    default:
      assert(0);
  }
}

void glopHint(GLContext* c, GLParam* p) {
#if 0
  int target=p[1].i;
  int mode=p[2].i;

  /* do nothing */
#endif
}

void glopPolygonOffset(GLContext* c, GLParam* p) {
  c->offset_factor = p[1].f;
  c->offset_units = p[2].f;
}
